[PATCH v2 22/27] nvdimm/ocxl: Implement the heartbeat command

[Alastair D'Silva]

On Mon, 2020-02-03 at 15:11 +0000, Jonathan Cameron wrote:
> On Tue, 3 Dec 2019 14:46:50 +1100
> Alastair D'Silva <alastair at au1.ibm.com> wrote:
> 
> > From: Alastair D'Silva <alastair at d-silva.org>
> > 
> > The heartbeat admin command is a simple admin command that
> > exercises
> > the communication mechanisms within the controller.
> > 
> > This patch issues a heartbeat command to the card during init to
> > ensure
> > we can communicate with the card's crontroller.
> 
> controller

That's a perfectly cromulent misspelling ;)

> 
> > Signed-off-by: Alastair D'Silva <alastair at d-silva.org>
> > ---
> >  drivers/nvdimm/ocxl/scm.c | 43
> > +++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 43 insertions(+)
> > 
> > diff --git a/drivers/nvdimm/ocxl/scm.c b/drivers/nvdimm/ocxl/scm.c
> > index 8a30c887b5ed..e8b34262f397 100644
> > --- a/drivers/nvdimm/ocxl/scm.c
> > +++ b/drivers/nvdimm/ocxl/scm.c
> > @@ -353,6 +353,44 @@ static bool scm_is_usable(const struct
> > scm_data *scm_data)
> >  	return true;
> >  }
> >  
> > +/**
> > + * scm_heartbeat() - Issue a heartbeat command to the controller
> > + * @scm_data: a pointer to the SCM device data
> > + * Return: 0 if the controller responded correctly, negative on
> > error
> > + */
> > +static int scm_heartbeat(struct scm_data *scm_data)
> > +{
> > +	int rc;
> > +
> > +	mutex_lock(&scm_data->admin_command.lock);
> > +
> > +	rc = scm_admin_command_request(scm_data,
> > ADMIN_COMMAND_HEARTBEAT);
> > +	if (rc)
> > +		goto out;
> > +
> > +	rc = scm_admin_command_execute(scm_data);
> > +	if (rc)
> > +		goto out;
> > +
> > +	rc = scm_admin_command_complete_timeout(scm_data,
> > ADMIN_COMMAND_HEARTBEAT);
> > +	if (rc < 0) {
> > +		dev_err(&scm_data->dev, "Heartbeat timeout\n");
> > +		goto out;
> > +	}
> > +
> > +	rc = scm_admin_response(scm_data);
> > +	if (rc < 0)
> > +		goto out;
> > +	if (rc != STATUS_SUCCESS)
> > +		scm_warn_status(scm_data, "Unexpected status from
> > heartbeat", rc);
> > +
> > +	rc = scm_admin_response_handled(scm_data);
> > +
> > +out:
> > +	mutex_unlock(&scm_data->admin_command.lock);
> > +	return rc;
> > +}
> > +
> >  /**
> >   * allocate_scm_minor() - Allocate a minor number to use for an
> > SCM device
> >   * @scm_data: The SCM device to associate the minor with
> > @@ -1508,6 +1546,11 @@ static int scm_probe(struct pci_dev *pdev,
> > const struct pci_device_id *ent)
> >  		goto err;
> >  	}
> >  
> > +	if (scm_heartbeat(scm_data)) {
> > +		dev_err(&pdev->dev, "SCM Heartbeat failed\n");
> > +		goto err;
> > +	}
> > +
> >  	elapsed = 0;
> >  	timeout = scm_data->readiness_timeout + scm_data-
> > >memory_available_timeout;
> >  	while (!scm_is_usable(scm_data)) {
-- 
Alastair D'Silva
Open Source Developer
Linux Technology Centre, IBM Australia
mob: 0423 762 819